Excerpt:
CO2 levels are now 50 percent higher than in pre-industrial times — a level not seen for 4 million years.
Every year at this time, headlines proclaim that carbon dioxide in the atmosphere has climbed to record high levels. But that really shouldn’t be all that surprising, given that CO2 has risen to a new high every single year but one since direct measurements began in 1958.
Now, however, an arguably more meaningful milestone has been passed.
